Field notes on data engineering and AI by Bruno Mentges — senior engineer writing about production systems, LLM integration, and platform design.https://bmentges.github.io/en-ushttps://bmentges.github.io/posts/knowledge-base-as-agentic-memory/https://bmentges.github.io/posts/knowledge-base-as-agentic-memory/Why AI coding agents produce dramatically better development plans when they have a structured wiki about your architecture, decisions, and concepts — and an open-source template to build one yourself.Fri, 17 Apr 2026 00:00:00 GMTai-agentsknowledge-basesecond-brainopen-sourcehttps://bmentges.github.io/posts/ai-agents-in-data-pipelines/https://bmentges.github.io/posts/ai-agents-in-data-pipelines/The agents were good. But they hit a ceiling I didn't expect — and the thing that broke through it wasn't a better model. It was a knowledge base.Thu, 16 Apr 2026 00:00:00 GMTai-agentsdata-engineeringmcpproductionhttps://bmentges.github.io/posts/mcp-agentic-workflows-guardrails/https://bmentges.github.io/posts/mcp-agentic-workflows-guardrails/What Model Context Protocol actually looks like in a real engineering workflow — how to set up context servers, build guardrails that earn trust, and integrate agents where they matter.Wed, 15 Apr 2026 00:00:00 GMTmcpai-agentsguardrailsproductionhttps://bmentges.github.io/posts/medallion-architecture-misunderstood/https://bmentges.github.io/posts/medallion-architecture-misunderstood/Everyone talks about bronze/silver/gold layers. Most implementations miss the point entirely. Here's what the pattern is actually for — and when to break the rules.Tue, 14 Apr 2026 00:00:00 GMTmedalliondata-architecturedbtwarehousehttps://bmentges.github.io/posts/building-data-platform-from-zero/https://bmentges.github.io/posts/building-data-platform-from-zero/What I learned designing and building a complete data platform for a growing company — from first table to production analytics. The decisions that matter, the order that works, and the mistakes everyone makes.Mon, 13 Apr 2026 00:00:00 GMTdata-platformdata-architecturebigquerygreenfieldhttps://bmentges.github.io/posts/petabyte-pipeline-cost-optimization/https://bmentges.github.io/posts/petabyte-pipeline-cost-optimization/Performance engineering at scale isn't about clever tricks — it's about understanding economics. A case study in Spark optimization, partition strategy, and thinking in dollars instead of milliseconds.Sun, 12 Apr 2026 00:00:00 GMTsparkoptimizationcostpetabyte-scalehttps://bmentges.github.io/posts/hackathon-tech-debt-bug-squash/https://bmentges.github.io/posts/hackathon-tech-debt-bug-squash/How a 2-day hackathon at a Brazilian e-commerce company squashed 70% of outstanding bugs and improved uptime from 92% to 99%. The real lesson isn't about hackathons — it's about permission.Sat, 11 Apr 2026 00:00:00 GMTtech-debthackathonengineering-cultureleadershiphttps://bmentges.github.io/posts/28-year-engineering-arc/https://bmentges.github.io/posts/28-year-engineering-arc/From telecoms in 1998 to AI-augmented data engineering in 2026. What stayed the same, what changed completely, and what I wish I'd known earlier.Fri, 10 Apr 2026 00:00:00 GMTcareerretrospectivedata-engineeringai-engineering